The Trial of Disinheritance (廃嫡裁判) was done by Geil Rugner so he could take over the throne and become the emperor of the Scarlet Moon Empire.
In the year 217 of the Scarlet Moon Calendar, the "War of Succession" began over the ascension to the throne. Barbarossa Rugner, the original heir to the throne, was deprived of his right to the throne by his uncle Geil Rugner, who initiated the "Trial of Disinheritance" to take advantage of Barbarossa's absence.